Our engines are single overhead cam engines. Variable valve timed engines require dual cams. One for the exhaust valvetrain and the other for intake so that the intake and exhaust valves can be contolled independantly. The benifit of variable valve timing is that the intake and exhaust valve overlap can be changed to produce better combustion and evacuation at higher rpm ranges. So I would have to say that we have fixed valve timing. Keep in mind that this engine has been around for something like 12 years (maybe longer, I'm not sure) with only some very minor changes.